Photo Tip: Shoot the Moon and Miss Completely

The exposure for this moon shot was calculated using the Sunny f-16 Rule. See article text.

Have you heard the song? Shoot the Moon by Norah Jones? How does any man listen to her sing and play her piano and not fall hopelessly in love with the woman? And it’s not just Shoot the Moon. I’ve got her album Come Away With Me in my music library and it’s the most listened to of all the albums I own.

In Shoot the Moon there’s a line, part of which is title of this Photo Tip. Have you ever seen a big, beautiful full moon in the dark night sky that you wanted to photograph but when you tried it came out over-exposed, all white with little or no detail? You may have a camera that makes terrific exposures most of the time but when you shoot the moon it misses completely, giving you disappointing exposures.

Here’s what’s going on: light meters in many of today’s digital cameras as well as more recent film cameras have many algorithms by which they guess at the optimum exposure for a given scene. The camera senses patterns of light and dark and tries to figure out what kind of scene you’re shooting. Landscape? Portrait? Night? Then it adjusts the exposure accordingly. Scenes such as the dark night sky with a bright moon in it are often not exposed very well by cameras because they don’t recognize what they are shooting. They try to lighten the dark areas but they do so at the expense of blowing out the moon. So, you shoot the moon and miss completely.

How do we fix this? There are different approaches. One is to set the camera to underexpose. This presumes, of course, that your camera has an adjustment that will allow you to do so, and that you know how set our camera. How much should you set the camera to underexpose I cannot say because of variables I cannot know such as how much of the frame the moon occupies in your viewfinder. Try 3 f-stops to begin with and check the results.

Perhaps a more surefire way is to use the Sunny f-16 Rule as your starting point. What’s that? It goes like this and it requires setting the camera manually: set your aperture to f-16. Then take the ISO (sometimes called film speed or sensitivity) your camera is set to (lower is always better for quality) and use that as the denominator in a fraction where one is the numerator. This gives you the shutter speed to use. If your camera is set to ISO 100 then use f-16 at 1/100th of second. If your camera is set to ISO 400, use f-16 at 1/400th of a second. This is a starting point for determining proper exposure. You can use the LCD on your camera to check the results if your camera is so equipped.

This rule can be used anytime you’re taking pictures on a bright sunny day. Huh? Bright sunny day? I thought we were shooting the moon and it’s nighttime. Well, it is… and it isn’t. It’s nighttime where we are but it’s daytime on the moon! The moon is lit by the sun. Isn’t it? Whooda thunkit?

Of course, you can use equivalent aperture/ISO combinations. If, for example you’re shooting at 1/100th of a second at f-16 as in the example above you could also shoot at 1/200th of a second at f-11, or 1/400th of a second at f-8.

Oh, and by the way, all of this means you can hand hold your camera and get a good sharp shot of the full moon, at night, without a tripod! If you’re using a telephoto lens then don’t hand hold at shutter speeds longer than 1 over the focal length of the lens. For example, if you’re using a 300mm lens then make sure to shoot at 1/300th of a second or shorter durations.

So, don’t shoot the moon and miss completely, unless of course your name is Norah Jones, in which case, marry me this instant!

What? Have you been spying on me? Perfect timing on this post. My moon shots from the other night didn’t turn out and my shots on a little photo excursion yesterday are all on the over exposed side. They look good on the cameras LCD screen but once downloaded on the computer not so good… grrr! I even used my polarizing filter. Oh well, tomorrows another day. Delete, adjust, and try again 😉

Sounds more like my timing was just a little late 🙂 My humblest of humble apologies 😉

Your camera may have a setting that allows you to dim or brighten your LCD screen. You might find a setting that more closely approximates what you see on your computer. That said, I can’t know if what you see on your computer is “correct” either. It could be the culprit. There is a whole area in photography that has to do with calibration–getting the brightness and colors of devices correct. If you’ve ever walked into a store selling televisions that had a number of them all tuned to the same channel you may have noticed disparities of brightness, color and contrast between them. Which one was correct? Were any of them correct? How can you tell?

When people get really serious about photography they buy monitors that are known to have favorable characteristics and which can be calibrated. They also buy color calibration hardware and software used to create profiles in order to match what they see on screen to what it should really look like and so they can make prints that closely approximate what they see on their screen.

I know, I know… more stuff one has to learn about and spend money on, but look at the bright side: more fun stuff to learn about, better control on one’s imagery and more toys!

One more thing: understanding and learning how to use the Histograms provided on many digital cameras is key to checking for proper or faulty exposure. It’s an über useful and valuable tool, and one I should write a tutorial about sometime.